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1.
J Environ Manage ; 356: 120502, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479281

RESUMO

Effective removal of phosphorus from water is crucial for controlling eutrophication. Meanwhile, the post-disposal of wetland plants is also an urgent problem that needs to be solved. In this study, seedpods of the common wetland plant lotus were used as a new raw material to prepare biochar, which were further modified by loading nano La(OH)3 particles (LBC-La). The adsorption performance of the modified biochar for phosphate was evaluated through batch adsorption and column adsorption experiments. Adsorption performance of lotus seedpod biochar was significantly improved by La(OH)3 modification, with adsorption equilibrium time shortened from 24 to 4 h and a theoretical maximum adsorption capacity increased from 19.43 to 52.23 mg/g. Moreover, LBC-La maintained a removal rate above 99% for phosphate solutions with concentrations below 20 mg/L. The LBC-La exhibited strong anti-interference ability in pH (3-9) and coexisting ion experiments, with the removal ratio remaining above 99%. The characterization analysis indicated that the main mechanism is the formation of monodentate or bidentate lanthanum phosphate complexes through inner sphere complexation. Electrostatic adsorption and ligand exchange are also the mechanisms of LBC-La adsorption of phosphate. In the dynamic adsorption experiment of simulated wastewater treatment plant effluent, the breakthrough point of the adsorption column was 1620 min, reaching exhaustion point at 6480 min, with a theoretical phosphorus saturation adsorption capacity of 6050 mg/kg. The process was well described by the Thomas and Yoon-Nelson models, which indicated that this is a surface adsorption process, without the internal participation of the adsorbent.


Assuntos
Lotus , Poluentes Químicos da Água , Fósforo , Águas Residuárias , Fosfatos/química , Carvão Vegetal , Adsorção , Lantânio/química , Poluentes Químicos da Água/química , Sementes , Cinética
2.
BMC Surg ; 23(1): 352, 2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980470

RESUMO

OBJECTIVE: The aim of this study was to investigate the clinical efficacy of small plate assisted anatomical plate and traditional double plate in the treatment of Rüedi and Allgöwer II - III pilon fracture. METHODS AND MATERIALS: The data of 68 patients with pilon fracture admitted to Hospital from June 2017 to June 2020 were retrospectively analyzed. Study group and control group were divided according to different operation methods, with 34 cases in each group. There were 28 cases of Rüedi and Allgöwer II type and 40 cases of Rüedi and Allgöwer III type. Perioperative period data, Ankle joint function score, visual analog scale (VAS) scores and the incidence of incision complications were analyzed between these two groups. RESULTS: There were no significant differences in full load time, fracture healing time between these two groups (P > 0.05). The operation time, intraoperative blood loss, length of hospital stay, Ankle joint function score and postoperative incision complication rate in observation group were lower than those in control group (P < 0.05). CONCLUSION: Small plate assisted anatomic plate is comparable to traditional double plate in the treatment of pilon fracture in terms of complete loading time, fracture healing time, but the former can shorten the operation time, reduce intraoperative blood loss and effectively reduce the incidence of postoperative complications.


Assuntos
Fraturas do Tornozelo , Fraturas da Tíbia , Humanos , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Fixação Interna de Fraturas/métodos , Fraturas da Tíbia/cirurgia , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Resultado do Tratamento , Complicações Pós-Operatórias
3.
Molecules ; 26(9)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33922916

RESUMO

A novel core-shell magnetic Prussian blue-coated Fe3O4 composites (Fe3O4@PB) were designed and synthesized by in-situ replication and controlled etching of iron oxide (Fe3O4) to eliminate Cd (II) from micro-polluted water. The core-shell structure was confirmed by TEM, and the composites were characterized by XRD and FTIR. The pore diameter distribution from BET measurement revealed the micropore-dominated structure of Fe3O4@PB. The effects of adsorbents dosage, pH, and co-existing ions were investigated. Batch results revealed that the Cd (II) adsorption was very fast initially and reached equilibrium after 4 h. A pH of 6 was favorable for Cd (II) adsorption on Fe3O4@PB. The adsorption rate reached 98.78% at an initial Cd (II) concentration of 100 µg/L. The adsorption kinetics indicated that the pseudo-first-order and Elovich models could best describe the Cd (II) adsorption onto Fe3O4@PB, indicating that the sorption of Cd (II) ions on the binding sites of Fe3O4@PB was the main rate-limiting step of adsorption. The adsorption isotherm well fitted the Freundlich model with a maximum capacity of 9.25 mg·g-1 of Cd (II). The adsorption of Cd (II) on the Fe3O4@PB was affected by co-existing ions, including Cu (II), Ni (II), and Zn (II), due to the competitive effect of the co-adsorption of Cd (II) with other co-existing ions.

4.
Microsc Microanal ; 25(2): 389-400, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30722805

RESUMO

We introduce an efficient, automated computational approach for analyzing interfaces within atom probe tomography datasets, enabling quantitative mapping of their thickness, composition, as well as the Gibbsian interfacial excess of each solute. Detailed evaluation of an experimental dataset indicates that compared with the composition map, the interfacial excess map is more robust and exhibits a relatively higher resolution to reveal compositional variations. By field evaporation simulations with a predefined emitter mimicking the experimental dataset, the impact of trajectory aberrations on the measurement of the thickness, composition, and interfacial excess of the decorated interface are systematically analyzed and discussed.

5.
J Pharmacol Exp Ther ; 358(3): 371-86, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27411717

RESUMO

To identify novel targets for neuropathic pain, 3097 mouse knockout lines were tested in acute and persistent pain behavior assays. One of the lines from this screen, which contained a null allele of the adapter protein-2 associated kinase 1 (AAK1) gene, had a normal response in acute pain assays (hot plate, phase I formalin), but a markedly reduced response to persistent pain in phase II formalin. AAK1 knockout mice also failed to develop tactile allodynia following the Chung procedure of spinal nerve ligation (SNL). Based on these findings, potent, small-molecule inhibitors of AAK1 were identified. Studies in mice showed that one such inhibitor, LP-935509, caused a reduced pain response in phase II formalin and reversed fully established pain behavior following the SNL procedure. Further studies showed that the inhibitor also reduced evoked pain responses in the rat chronic constriction injury (CCI) model and the rat streptozotocin model of diabetic peripheral neuropathy. Using a nonbrain-penetrant AAK1 inhibitor and local administration of an AAK1 inhibitor, the relevant pool of AAK1 for antineuropathic action was found to be in the spinal cord. Consistent with these results, AAK1 inhibitors dose-dependently reduced the increased spontaneous neural activity in the spinal cord caused by CCI and blocked the development of windup induced by repeated electrical stimulation of the paw. The mechanism of AAK1 antinociception was further investigated with inhibitors of α2 adrenergic and opioid receptors. These studies showed that α2 adrenergic receptor inhibitors, but not opioid receptor inhibitors, not only prevented AAK1 inhibitor antineuropathic action in behavioral assays, but also blocked the AAK1 inhibitor-induced reduction in spinal neural activity in the rat CCI model. Hence, AAK1 inhibitors are a novel therapeutic approach to neuropathic pain with activity in animal models that is mechanistically linked (behaviorally and electrophysiologically) to α2 adrenergic signaling, a pathway known to be antinociceptive in humans.


Assuntos
Neuralgia/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Masculino , Camundongos , Neuralgia/metabolismo , Neuralgia/fisiopatologia , Nociceptividade/efeitos dos fármacos , Fenótipo , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Ratos , Medula Espinal/efeitos dos fármacos , Medula Espinal/enzimologia , Medula Espinal/fisiopatologia
6.
J Transl Med ; 14: 48, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26867596

RESUMO

BACKGROUND: Previous studies suggest that certain transition metal complexes, such as cisplatin, are efficacious for treating various cancer types, including ovarian, lung, and breast. METHODS: In order to further evaluate ruthenium (Ru) complexes as potential anti-cancer agents, we synthesized and evaluated Ru-arene complexes. Two complexes with the general formula [Ru (η (6)-p-cym) (N-N) Cl](+) were tested for their abilities to inhibit cancer cells. RESULTS: The complex with o-phenylenediamine as the N-N ligand (o-PDA) significantly inhibited growth of breast (MDA-MB-231, MCF-7, SKBR-3, and SUM149), lymphoma (Raji), melanoma (Bowes), and osteosarcoma (HT1080); however, the complex with o-benzoquinonediimine (o-BQDI) was ineffective except for SUM149. In contrast, o-PDA failed to inhibit growth of human breast epithelial cells, MCF-10A. Treatment of MDA-MBA-231 cells with o-PDA resulted in a significant reduction of productions of PDGF-AA, GM-CSF, and VEGF-A proteins at the transcriptional levels. Finally, we demonstrated that o-PDA synergistically inhibited MDA-MB-231 cell growth with cyclophosphamide but not doxorubicin or paclitaxel. CONCLUSION: These results suggest that Ru-arene complexes are promising anti-cancer drugs that inhibit progression and metastasis by blocking multiple processes for breast and other types of cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Complexos de Coordenação/uso terapêutico , Rutênio/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Fenilenodiaminas/farmacologia , Rutênio/química , Rutênio/farmacologia
7.
Environ Sci Technol ; 50(7): 4054-60, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26950772

RESUMO

Microplastics have become emerging contaminants, causing widespread concern about their potential toxic effects. In this study, the uptake and tissue accumulation of polystyrene microplastics (PS-MPs) in zebrafish were detected, and the toxic effects in liver were investigated. The results showed that after 7 days of exposure, 5 µm diameter MPs accumulated in fish gills, liver, and gut, while 20 µm diameter MPs accumulated only in fish gills and gut. Histopathological analysis showed that both 5 µm and 70 nm PS-MPs caused inflammation and lipid accumulation in fish liver. PS-MPs also induced significantly increased activities of superoxide dismutase and catalase, indicating that oxidative stress was induced after treatment with MPs. In addition, metabolomic analysis suggested that exposure to MPs induced alterations of metabolic profiles in fish liver and disturbed the lipid and energy metabolism. These findings provide new insights into the toxic effects of MPs on fish.


Assuntos
Fígado/metabolismo , Plásticos/toxicidade , Poliestirenos/metabolismo , Poliestirenos/toxicidade , Peixe-Zebra/metabolismo , Animais , Análise Discriminante , Corantes Fluorescentes/metabolismo , Brânquias/efeitos dos fármacos , Análise dos Mínimos Quadrados , Fígado/efeitos dos fármacos , Masculino , Metaboloma/efeitos dos fármacos , Metabolômica , Estresse Oxidativo/efeitos dos fármacos
8.
Curr Cancer Drug Targets ; 24(5): 510-518, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38099524

RESUMO

BACKGROUND: Liver cancer is one of the most prevalent forms of cancer of the digestive system in our country. The most common subtype of this disease is hepatocellular carcinoma (HCC). Currently, treatment options for HCC patients include surgical resection, liver transplantation, radiofrequency ablation, chemoembolization, and biologic-targeted therapy. However, the efficacy of these treatments is suboptimal, as they are prone to drug resistance, metastasis, spread, and recurrence. These attributes are closely related to cancer stem cells (CSCs). Therefore, the utilization of drugs targeting CSCs may effectively inhibit the development and recurrence of HCC. METHODS: HepG2 and Huh7 cells were used to analyze the antitumor activity of emodin by quantifying cell growth and metastasis, as well as to study its effect on stemness. RESULTS: Emodin effectively suppressed the growth and movement of HCC cells. Emodin also significantly inhibited the proliferation of CD44-positive hepatoma cells. CONCLUSION: Emodin shows promise as a potential therapeutic agent for HCC by targeting CD44-- positive hepatoma cells.


Assuntos
Carcinoma Hepatocelular , Proliferação de Células , Emodina , Receptores de Hialuronatos , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Humanos , Emodina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Receptores de Hialuronatos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células Hep G2 , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia
9.
Nat Neurosci ; 27(3): 561-572, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38243089

RESUMO

Episodic memories are encoded by experience-activated neuronal ensembles that remain necessary and sufficient for recall. However, the temporal evolution of memory engrams after initial encoding is unclear. In this study, we employed computational and experimental approaches to examine how the neural composition and selectivity of engrams change with memory consolidation. Our spiking neural network model yielded testable predictions: memories transition from unselective to selective as neurons drop out of and drop into engrams; inhibitory activity during recall is essential for memory selectivity; and inhibitory synaptic plasticity during memory consolidation is critical for engrams to become selective. Using activity-dependent labeling, longitudinal calcium imaging and a combination of optogenetic and chemogenetic manipulations in mouse dentate gyrus, we conducted contextual fear conditioning experiments that supported our model's predictions. Our results reveal that memory engrams are dynamic and that changes in engram composition mediated by inhibitory plasticity are crucial for the emergence of memory selectivity.


Assuntos
Consolidação da Memória , Memória Episódica , Camundongos , Animais , Consolidação da Memória/fisiologia , Rememoração Mental/fisiologia , Neurônios/fisiologia , Medo/fisiologia
10.
J Sep Sci ; 36(16): 2615-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23907746

RESUMO

A rapid method for the selective determination of four kinds of tobacco-specific nitrosamines, N-nitrosonornicotine, N-nitrosoanatabine, N-nitrosoanabasine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, in mainstream cigarette smoke was developed by GC coupled to positive chemical ionization triple-quadrupole MS. After mainstream cigarette smoke was collected on a cambridge filter pad, the particulate matter was extracted with 0.1 M HCL aqueous solution, cleaned by positive cation-exchange solid extraction, and finally injected into GC-MS/MS using isotopically labeled analogues as internal standards. Excellent linearity was obtained over the concentration range of 0.5-200.0 ng mL(-1) for all tobacco-specific nitrosamines with values for correlation coefficient between 0.9996-0.9999. Limits of detection of each tobacco specific nitrosamine varied from 0.023-0.028 ng cig(-1), and lower limits of quantification varied from 0.077-0.093 ng cig(-1). The recovery of each tobacco specific nitrosamine was from 90.0-109.0%. The relative standard deviations of the intra-day and inter-day precisions were 3.1-5.8 and 3.9-6.6, respectively. This method was applied to reference and domestic cigarettes. The result showed that the method was consistent with traditional methods and can be used as an effective approach for the routine analysis of tobacco-specific nitrosamines.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Nicotiana/química , Nitrosaminas/análise , Fumaça/análise , Produtos do Tabaco/análise , Espectrometria de Massas por Ionização por Electrospray/métodos
11.
Sensors (Basel) ; 13(5): 5881-96, 2013 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-23698266

RESUMO

Surface waves are commonly used for vibration-based nondestructive testing for infrastructure. Spectral Analysis of Surface Waves (SASW) has been used to detect subsurface properties for geologic inspections. Recently, efforts were made to scale down these subsurface detection approaches to see how they perform on small-scale structures such as concrete slabs and pavements. Additional efforts have been made to replace the traditional surface-mounted transducers with non-contact acoustic transducers. Though some success has been achieved, most of these new approaches are inefficient because they require point-to-point measurements or off-line signal analysis. This article introduces a Mobile Acoustic Subsurface Sensing system as MASS, which is an improved surface wave based implementation for measuring the subsurface profile of roadways. The compact MASS system is a 3-wheeled cart outfitted with an electromagnetic impact source, distance register, non-contact acoustic sensors and data acquisition/ processing equipment. The key advantage of the MASS system is the capability to collect measurements continuously at walking speed in an automatic way. The fast scan and real-time analysis advantages are based upon the non-contact acoustic sensing and fast air-coupled surface wave analysis program. This integration of hardware and software makes the MASS system an efficient mobile prototype for the field test.

12.
PLoS One ; 18(8): e0289970, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37611031

RESUMO

The blood brain barrier (BBB) efficiently limits the penetration of biologics drugs from blood to brain. Establishment of an in vitro BBB model can facilitate screening of central nervous system (CNS) drug candidates and accelerate CNS drug development. Despite many established in vitro models, their application to biologics drug selection has been limited. Here, we report the evaluation of in vitro transcytosis of anti-human transferrin receptor (TfR) antibodies across human, cynomolgus and mouse species. We first evaluated human models including human cerebral microvascular endothelial cell line hCMEC/D3 and human colon epithelial cell line Caco-2 models. hCMEC/D3 model displayed low trans-epithelial electrical resistance (TEER), strong paracellular transport, and similar transcytosis of anti-TfR and control antibodies. In contrast, the Caco-2 model displayed high TEER value and low paracellular transport. Anti-hTfR antibodies demonstrated up to 70-fold better transcytosis compared to control IgG. Transcytosis of anti-hTfR.B1 antibody in Caco-2 model was dose-dependent and saturated at 3 µg/mL. Enhanced transcytosis of anti-hTfR.B1 was also observed in a monkey brain endothelial cell based (MBT) model. Importantly, anti-hTfR.B1 showed relatively high brain radioactivity concentration in a non-human primate positron emission tomography study indicating that the in vitro transcytosis from both Caco-2 and MBT models aligns with in vivo brain exposure. Typically, brain exposure of CNS targeted biologics is evaluated in mice. However, antibodies, such as the anti-human TfR antibodies, do not cross-react with the mouse target. Therefore, validation of a mouse in vitro transcytosis model is needed to better understand the in vitro in vivo correlation. Here, we performed transcytosis of anti-mouse TfR antibodies in mouse brain endothelial cell-based models, bEnd3 and the murine intestinal epithelial cell line mIEC. There is a good correlation between in vitro transcytosis of anti-mTfR antibodies and bispecifics in mIEC model and their mouse brain uptake. These data strengthen our confidence in the predictive power of the in vitro transcytosis models. Both mouse and human in vitro models will serve as important screening assays for brain targeted biologics selection in CNS drug development.


Assuntos
Produtos Biológicos , Animais , Camundongos , Humanos , Células CACO-2 , Tomografia Computadorizada por Raios X , Encéfalo , Transcitose
13.
Food Chem ; 414: 135561, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36827781

RESUMO

Organic macromolecules form carcinogenic and toxic substances such as polycyclic aromatic hydrocarbons (PAHs) under high temperature baking. Thus, this study investigated the effects and inhibition pathways of different curcumin concentrations (0.01, 0.05, 0.25, 0.3 mg/g) on seven PAHs in grilled chicken wings. The results demonstrated that curcumin concentrations displayed positive effects in inhibiting the formation of PAHs (16%-72%), increasing the total phenolic content (397.5-1934.4 mg/g) and free radical scavenging activity, and reducing TBARS values (31.15%-47.76%) and fatty acid content. Additionally, PCA and Pearson correlation analyses indicated that lipid oxidation (r = 0.42) and unsaturated fatty acids (r = 0.55) could promote the production of PAHs, while DPPH, ABTS and TPC could counteract their facilitation of PAHs. In conclusion, the addition of appropriate amounts of curcumin before grilling is a feasible strategy to reduce fat oxidation levels and the number of free radicals for the purpose of limiting PAHs content.


Assuntos
Curcumina , Hidrocarbonetos Policíclicos Aromáticos , Animais , Galinhas , Curcumina/farmacologia , Curcumina/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Culinária/métodos , Temperatura Alta
14.
Front Bioeng Biotechnol ; 11: 1103611, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36733970

RESUMO

Stem cell-based therapy has drawn attention as an alternative option for promoting prosthetic osteointegration in osteoporosis by virtue of its unique characteristics. However, estrogen deficiency is the main mechanism of postmenopausal osteoporosis. Estrogen, as an effective antioxidant, deficienncy also results in the accumulation of reactive oxygen species (ROS) in the body, affecting the osteogenic differentiation of stem cells and the bone formation i osteoporosis. In this study, we prepared a ROS-scavenging hydrogel by crosslinking of epigallocatechin-3-gallate (EGCG), 3-acrylamido phenylboronic acid (APBA) and acrylamide. The engineered hydrogel can scavenge ROS efficiently, enabling it to be a cell carrier of bone marrow-derived mesenchymal stem cells (BMSCs) to protect delivered cells from ROS-mediated death and osteogenesis inhibition, favorably enhancing the tissue repair potential of stem cells. Further in vivo investigations seriously demonstrated that this ROS-scavenging hydrogel encapsulated with BMSCs can prominently promote osteointegration of 3D printed microporous titanium alloy prosthesis in osteoporosis, including scavenging accumulated ROS, inducing macrophages to polarize toward M2 phenotype, suppressing inflammatory cytokines expression, and improving osteogenesis related markers (e.g., ALP, Runx-2, COL-1, BSP, OCN, and OPN). This work provides a novel strategy for conquering the challenge of transplanted stem cells cannot fully function in the impaired microenvironment, and enhancing prosthetic osteointegration in osteoporosis.

15.
Chemosphere ; 286(Pt 2): 131773, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34375827

RESUMO

La(OH)3-modified canna biochar (CBC-La) was prepared by a coprecipitation method (dipping method), and its phosphate adsorption characteristics were investigated. The results show that the pseudo-second-order kinetics and the Langmuir model can be used to describe the adsorption process with a high level of accuracy. Adsorption equilibrium could be reached at 8 h, at which point the maximum adsorption capacity was shown to be 37.37 mg/g. CBC-La has excellent phosphate adsorption capacity in the middle to low concentrations (≤50 mg/L), and its removal rate can exceed 99 %. CBC-La also has wide pH adaptability (3-9) and a strongly selective adsorption performance. Notably, it can still maintain a removal rate of over 99.8 % in the presence of certain anions (NO3-, HCO3-, and CO32-), and the presence of NH4+ has a synergistic effect on the adsorption process. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) measurements demonstrate that the main mechanisms of CBC-La phosphate adsorption are electrostatic adsorption, ion exchange, ligand exchange and inner sphere complexation.


Assuntos
Poluentes Químicos da Água , Zingiberales , Adsorção , Carvão Vegetal , Cinética , Lantânio , Fosfatos , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Mol Ther Nucleic Acids ; 29: 625-642, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36090761

RESUMO

Tau is a microtubule-associated protein (MAPT, tau) implicated in the pathogenesis of tauopathies, a spectrum of neurodegenerative disorders characterized by accumulation of hyperphosphorylated, aggregated tau. Because tau pathology can be distinct across diseases, a pragmatic therapeutic approach may be to intervene at the level of the tau transcript, as it makes no assumptions to mechanisms of tau toxicity. Here we performed a large library screen of locked-nucleic-acid (LNA)-modified antisense oligonucleotides (ASOs), where careful tiling of the MAPT locus resulted in the identification of hot spots for activity in the 3' UTR. Further modifications to the LNA design resulted in the generation of ASO-001933, which selectively and potently reduces tau in primary cultures from hTau mice, monkey, and human neurons. ASO-001933 was well tolerated and produced a robust, long-lasting reduction in tau protein in both mouse and cynomolgus monkey brain. In monkey, tau protein reduction was maintained in brain for 20 weeks post injection and corresponded with tau protein reduction in the cerebrospinal fluid (CSF). Our results demonstrate that LNA-ASOs exhibit excellent drug-like properties and sustained efficacy likely translating to infrequent, intrathecal dosing in patients. These data further support the development of LNA-ASOs against tau for the treatment of tauopathies.

18.
Nat Med ; 10(9): 959-65, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15286784

RESUMO

Inhibiting the activity of the beta-amyloid converting enzyme 1 (BACE1) or reducing levels of BACE1 in vivo decreases the production of amyloid-beta. The reticulon family of proteins has four members, RTN1, RTN2, RTN3 and RTN4 (also known as Nogo), the last of which is well known for its role in inhibiting neuritic outgrowth after injury. Here we show that reticulon family members are binding partners of BACE1. In brain, BACE1 mainly colocalizes with RTN3 in neurons, whereas RTN4 is more enriched in oligodendrocytes. An increase in the expression of any reticulon protein substantially reduces the production of Abeta. Conversely, lowering the expression of RTN3 by RNA interference increases the secretion of Abeta, suggesting that reticulon proteins are negative modulators of BACE1 in cells. Our data support a mechanism by which reticulon proteins block access of BACE1 to amyloid precursor protein and reduce the cleavage of this protein. Thus, changes in the expression of reticulon proteins in the human brain are likely to affect cellular amyloid-beta and the formation of amyloid plaques.


Assuntos
Peptídeos beta-Amiloides/biossíntese , Ácido Aspártico Endopeptidases/metabolismo , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Secretases da Proteína Precursora do Amiloide , Precursor de Proteína beta-Amiloide , Sequência de Bases , Western Blotting , Proteínas de Transporte/genética , Primers do DNA , Endopeptidases/metabolismo , Biblioteca Gênica , Humanos , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Microscopia de Fluorescência , Dados de Sequência Molecular , Proteínas da Mielina , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Proteínas Nogo , Oligodendroglia/metabolismo , Nexinas de Proteases , Interferência de RNA , Receptores de Superfície Celular , Análise de Sequência de DNA
19.
J Intensive Care ; 9(1): 68, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702376

RESUMO

BACKGROUND: Although the associations between obesity, glucose variability (GV), and Intensive Care Unit (ICU) mortality have been studied extensively, whether age moderates these associations is not well understood. MATERIALS AND METHODS: The medical records of 1062 patients, who were admitted into ICU at Sir Run Run Shaw Hospital (Zhejiang, China), were studied. Logistic regression was used to test the associations between obesity, GV, and ICU mortality. Furthermore, the moderation effect of age was tested. RESULTS: After controlling for covariates, the underweight group had the highest odds of death (OR 2.38, 95% CI 1.43-3.95, p < 0.001) in comparison with the control group (overweight). However, normal weight (OR 1.29, 95% CI 0.88-1.89, p = 0.185) and obese (OR 1.08, 95% CI 0.61-1.90, p = 0.790) groups had similar odds of death, compared to the overweight group. Age significantly moderated the association between obesity and mortality, where being overweight was more advantageous than being normal weight in older adults (B = 0.03, SE = 0.01, OR 1.03, 95% CI 1.001-1.06, p = 0.045). Meanwhile, higher GV predicted greater mortality in adjusted models (OR 1.23, 95% CI 1.06-1.42, p = 0.005). We also found an interaction between age and GV (B = - 0.01, SE = 0.01, OR 0.99, 95% CI 0.98-0.999, p = 0.025), which suggested that the association between GV and mortality becomes weaker with increasing age. CONCLUSIONS: With increasing age, the association between BMI and mortality becomes stronger and the association between glucose variability and mortality becomes weaker. Future studies should investigate the underlying mechanisms of such phenomenon and the causal relationship between obesity, GV, and ICU mortality.

20.
Oxid Med Cell Longev ; 2021: 6219715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765084

RESUMO

BACKGROUND: Mesenchymal stem cell-derived exosomes (MSC-exos) have been recognized as a promising therapeutic strategy for neonatal hypoxic-ischemic brain damage (HIBD). Recently, microglial pyroptosis was shown to play a vital role in the progression of neonatal HIBD. However, whether MSC-exos improve HIBD by regulating microglial pyroptosis remains unknown. METHODS: Exosomes were isolated from human umbilical cord mesenchymal stem cells (huMSCs) and identified by transmission electron microscopy (TEM), western blot, and nanoparticle tracking analysis (NTA). BV-2 cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to induce microglial ischemia/reperfusion (I/R) in vitro. CCK-8, ELISA, western blot, and Hoechst 33342/PI double staining were performed to detect the pyroptosis of BV-2 cells. Conditioned medium (CM) from BV-2 cells exposed to different treatments was used to investigate its effect on neuronal injury. Moreover, 3-methyladenine (3-MA) and mitochondrial division inhibitor-1 (mdi-1) were used to verify the involvement of mitophagy in the protection of MSC-exos against OGD/R-induced pyroptosis in BV-2 cells. Finally, FOXO3a siRNA was used to investigate the involvement of FOXO3a in MSC-exo-induced mitophagy and pyroptosis inhibition. RESULTS: Exosomes from huMSCs were successfully extracted. In OGD/R-exposed BV-2 cells, MSC-exos increased cell viability and decreased the expression of NLRP3, cleaved caspase-1, and GSDMD-N as well as the release of IL-1ß and IL-18. Compared with CM from OGD/R-exposed BV-2 cells treated with PBS, CM from OGD/R-exposed BV-2 cells treated with MSC-exos significantly increased the viability of SH-SY5Y cells and decreased LDH release. MSC-exos also increased the expression of TOM20 and COX IV in OGD/R-exposed BV-2 cells. Additionally, 3-MA and mdi-1 attenuated the inhibition of pyroptosis with MSC-exo treatment. Furthermore, FOXO3a siRNA partially abolished the neuroprotective effect of MSC-exos and attenuated mitophagy and pyroptosis inhibition induced by MSC-exo treatment. CONCLUSIONS: Our findings demonstrated that MSC-exos increased FOXO3a expression to enhance mitophagy, therefore protecting microglia from I/R-induced pyroptosis and alleviating subsequent neuronal injury.


Assuntos
Exossomos/fisiologia , Proteína Forkhead Box O3/metabolismo , Microglia/citologia , Mitofagia , Neuroblastoma/prevenção & controle , Piroptose , Traumatismo por Reperfusão/prevenção & controle , Glucose/deficiência , Humanos , Hipóxia/fisiopatologia , Células-Tronco Mesenquimais/citologia , Microglia/metabolismo , Microglia/patologia , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Cordão Umbilical/citologia
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